DataBatrix » XML

Populate TreeView From Custom Object Using Serializer

Eric — Tue, 21 Dec 2010 17:40:41 +0000

From time to time I need to spit out the public properties of an object for various reasons. A typical use would be to show user friendly results from a web service that returns a complex object. There could be tons of other uses! After doing this a few times, I finially decided to post this so I can always reference it. Anytime I do any recursive methods, it always takes me a couple of tweaks before getting it right.

The idea is that I have a custom object that I need to spin through to populate a TreeView. I created a couple of simple methods to do such. I though about using Reflection, but my method starting getting larger and larger because I was having to put in special code to handle certain Types (i.e. String, ICollection, etc). Since my typical Use Case was to spit out the results of a complex object returned from a ASMX or WCF service, I decided to go the Serialize route. My DTO class was typically already decorated with the [Serializable] attribute, if not, it was simple enought to add.

So first we serialize the object into a string of XML, then stuff that into a XmlDocument. Then you can loop through the elements while creating each TreeViewNode. That’s it!

        public void PopulateTreeView(object obj, TreeView tv)
        {
            System.Xml.Serialization.XmlSerializer serializer = new System.Xml.Serialization.XmlSerializer(obj.GetType());
            System.Text.StringBuilder sb = new System.Text.StringBuilder();  // StringBuilder to hold the XML
            using (System.Xml.XmlWriter writer = System.Xml.XmlWriter.Create(sb))
            {
                serializer.Serialize(writer, obj); // Serialize the object to XML
                System.Xml.XmlDocument xDoc = new System.Xml.XmlDocument();
                xDoc.LoadXml(sb.ToString());  // Shove it in a XmlDocument
                tv.Nodes.Add(PopulateNode(xDoc));  // Add the Nodes to the TreeView
            }
        }

        public TreeNode PopulateNode(System.Xml.XmlNode node)
        {
            TreeNode treenode = new TreeNode(node.Name);  // Add the Name to the Node
            if (node.ChildNodes.Count == 1) //Prevents ParentNode from displaying all of the InnerText
                treenode.Text += "=" + node.InnerText; // If only 1 ChildNode then add the InnerText

            for (int i = 0; i < node.ChildNodes.Count; i++)
            {
                if (node.ChildNodes[i].HasChildNodes)
                {
                    treenode.ChildNodes.Add(PopulateNode(node.ChildNodes[i]));
                }
            }
            return treenode;
        }

Then call the method to populate where “customObject” is the object you want displayed in your TreeView:

            PopulateTreeView(customObject, TreeView1);

.NET Serialization: Binary, SOAP, and XML (VB)

Eric — Thu, 08 Oct 2009 23:43:50 +0000

In .NET when you need to shrink an object into a more portable format you have 3 choices. Binary, SOAP, or XML. The process of shrinking and expanding the object is called serialization and deserialization. Each option has it’s own advantages which I will explain.

Binary

You can serialize an object into binary format quite easily using the .NET Framework. This is the quickest and smallest way to serialize; however, the binary format can only be deserialized using the same .NET Framework. This may be a problem for interoperability. It must be noted that this format will serialize Public and Private members (unlike XML serialization).

The example below shows how to serialize an object called “newCustomer”:

        Dim newCustomer As Contact = GetSampleContact()

        Using fs As New IO.FileStream(filePathandName & ".bin", IO.FileMode.Create)
            Dim binFormatter As New Runtime.Serialization.Formatters.Binary.BinaryFormatter()
            binFormatter.Serialize(fs, newCustomer)
        End Using

And here is the reverse to deserialize:

        Dim readCustomer As Contact

        Using fs As New IO.FileStream(filePathandName & ".bin", IO.FileMode.Open, IO.FileAccess.Read)
            Dim binFormatter As New Runtime.Serialization.Formatters.Binary.BinaryFormatter()
            readCustomer = CType(binFormatter.Deserialize(fs), Contact)
        End Using

SOAP

SOAP is another method. This is similar to the binary method except the serialized data is stored in a standardized form (SOAP) which will easily allow interoperability. Public and Private members are serialized using this method as well.
To serialize:

        Dim newCustomer As Contact = GetSampleContact()
        Using fs As New IO.FileStream(filePathandName & "SOAP.xml", IO.FileMode.Create)
            Dim soapFormattter As New Runtime.Serialization.Formatters.Soap.SoapFormatter()
            soapFormattter.Serialize(fs, newCustomer)
        End Using

And to deserialize:

        Dim readCustomer As Contact
        Using fs As New IO.FileStream(filePathandName & "SOAP.xml", IO.FileMode.Open, IO.FileAccess.Read)
            Dim soapFormattter As New Runtime.Serialization.Formatters.Soap.SoapFormatter()
            readCustomer = CType(soapFormattter.Deserialize(fs), Contact)
        End Using

XML

A third choice is using the XMLSerializer class. This method will only serialize Public properties and members and the object must be marked with the Serializable attribute and contain an empty constructor. This method of serialization will be smaller in size than the SOAP method since less information is serialized. Here is an example of such class:

      Class Contact

        Private _FirstName As String
        Public Property FirstName() As String
            Get
                Return _FirstName
            End Get
            Set(ByVal value As String)
                _FirstName = value
            End Set
        End Property

        Private _LastName As String
        Public Property LastName() As String
            Get
                Return _LastName
            End Get
            Set(ByVal value As String)
                _LastName = value
            End Set
        End Property

        Private _MiddleI As String
        Public Property MiddleI() As String
            Get
                Return _MiddleI
            End Get
            Set(ByVal value As String)
                _MiddleI = value
            End Set
        End Property

        Private _PIN As String
        Public WriteOnly Property PIN() As String
            Set(ByVal value As String)
                _PIN = value
            End Set
        End Property

        Sub New()

        End Sub

        Sub New(ByVal fName As String, ByVal middleI As String, ByVal lName As String, ByVal p As String)
            _FirstName = fName
            _MiddleI = middleI
            _LastName = lName
            _PIN = p
        End Sub
    End Class

Here is how you would serialize using the XMLSerializer:

        Dim newCustomer As Contact = GetSampleContact()
        Using fs As New IO.FileStream(filePathandName & ".xml", IO.FileMode.Create)
            Dim xmlFormatter As New Xml.Serialization.XmlSerializer(GetType(Contact))
            xmlFormatter.Serialize(fs, newCustomer)
        End Using

And to deserialize:

        Dim readCustomer As Contact
        Using fs As New IO.FileStream(filePathandName & ".xml", IO.FileMode.Open, IO.FileAccess.Read)
            Dim xmlFormatter As New Xml.Serialization.XmlSerializer(GetType(Contact))
            readCustomer = CType(xmlFormatter.Deserialize(fs), Contact)
        End Using

You can download a sample serialization demo project that I created to demonstrate: SerializationDemoProject.zip.

A .NET Bit.ly API Helper Class (Visual Basic.NET)

Eric — Mon, 24 Aug 2009 21:19:19 +0000

I decided to write a helper class for using the Bit.ly API for creating short urls. You know, those tiny links that you see all over Facebook, Twitter, etc. The snippet below shows how you would use the helper class. Not only can you shorten an url, you can shorted multiple urls in a single call as well as get stats and info about a bit.ly url. If you are looking to incorporate bit.ly short urls in your application using their API access, this will save you some time. The class uses the XmlSerializer for reading bit.ly’s response.

        ' Pass username and API key to instantiate
        Dim newbitlyAPI As New DataBatrix.bitlyAPI.bitlyAPI("bitlyapidemo", "R_0da49e0a9118ff35f52f629d2d71bf07")

        ' Sample of creating 1 short URL
        Dim shortenResponse As DataBatrix.bitlyAPI.bitlyShortenResponse = newbitlyAPI.Shorten("http://www.databatrix.com")
        Dim shortURL As String = ""
        If shortenResponse.results.Count > 0 Then
            shortURL = shortenResponse.results(0).shortUrl
        End If

        ' Sample of creating multiple short URLs
        Dim longUrls() As String = {"http://www.databatrix.com", "http://www.google.com"}
        Dim shortenResponses As DataBatrix.bitlyAPI.bitlyShortenResponse = newbitlyAPI.Shorten(longUrls)
        Dim shortURLs(1) As String
        For i As Integer = 0 To shortenResponses.results.Count - 1
            shortURLs(i) = shortenResponses.results(i).shortUrl

        Next

        ' Sample of getting bit.ly info...
        Dim info As DataBatrix.bitlyAPI.bitlyInfoResponse = newbitlyAPI.Info("2bYgqR")

        ' Sample of getting bit.ly stats...
        Dim stats As DataBatrix.bitlyAPI.bitlyStatsResponse = newbitlyAPI.Stats("http://bit.ly/1RmnUT")

Below is the helper class that I created. You can download the VB file bitlyAPI.vb or a sample project TestBitly Project Files.

Imports System.Web
Imports System.Xml
Imports System.Xml.Serialization

Namespace DataBatrix.bitlyAPI
    Public Class bitlyAPI
        Const BaseAPIUrl As String = "http://api.bit.ly/"
        Const version As String = "2.0.1"
        Const format As String = "xml"

        Public login As String = String.Empty
        Public apiKey As String = String.Empty

        Sub New(ByVal login As String, ByVal apiKey As String)
            Me.login = login
            Me.apiKey = apiKey

        End Sub

        Private Function BuildBaseRequestURL(ByVal applicationName As String) As System.Text.StringBuilder
            Dim RequestUrl As New System.Text.StringBuilder()
            With RequestUrl
                .Append(BaseAPIUrl & HttpUtility.UrlEncode(applicationName) & "?")
                .Append("version=" & HttpUtility.UrlEncode(version) & "&")
                .Append("format=" & HttpUtility.UrlEncode(format) & "&")
                .Append("login=" & HttpUtility.UrlEncode(login) & "&")
                .Append("apiKey=" & HttpUtility.UrlEncode(apiKey) & "&")
            End With
            Return RequestUrl
        End Function

        Public Function Shorten(ByVal longUrl As String) As bitlyShortenResponse
            Dim logUrls() As String = {longUrl}
            Return Shorten(logUrls)
        End Function

        Public Function Shorten(ByVal longUrl() As String) As bitlyShortenResponse
            Dim RequestUrl As System.Text.StringBuilder = BuildBaseRequestURL("shorten")
            For Each s As String In longUrl
                RequestUrl.Append("&longUrl=" & HttpUtility.UrlEncode(s))

            Next
            Dim responseObj As DataBatrix.bitlyAPI.bitlyShortenResponse = Nothing
            Try
                Dim serializer = New XmlSerializer(GetType(DataBatrix.bitlyAPI.bitlyShortenResponse))
                Using reader As XmlTextReader = New XmlTextReader(RequestUrl.ToString())
                    responseObj = CType(serializer.Deserialize(reader), DataBatrix.bitlyAPI.bitlyShortenResponse)
                End Using

            Catch ex As Exception

            End Try

            If responseObj.errorCode > 0 Then
                Throw New ApplicationException("Error from bit.ly: " & responseObj.errorMessage)
            End If
            Return responseObj
        End Function
        Public Function Info(ByVal hash As String) As bitlyInfoResponse
            Dim RequestUrl As System.Text.StringBuilder = BuildBaseRequestURL("info")
            With RequestUrl
                .Append("hash=" & HttpUtility.UrlEncode(hash))
            End With

            Dim responseObj As DataBatrix.bitlyAPI.bitlyInfoResponse = Nothing
            Try
                Dim serializer = New XmlSerializer(GetType(DataBatrix.bitlyAPI.bitlyInfoResponse))
                Using reader As XmlTextReader = New XmlTextReader(RequestUrl.ToString())
                    responseObj = CType(serializer.Deserialize(reader), DataBatrix.bitlyAPI.bitlyInfoResponse)
                End Using

            Catch ex As Exception
                Throw New ApplicationException("API Error: " & ex.Message)
            End Try
            If responseObj.errorCode > 0 Then
                Throw New ApplicationException("Error from bit.ly: " & responseObj.errorMessage)
            End If
            Return responseObj
        End Function

        Public Function Stats(ByVal shortUrl As String) As bitlyStatsResponse
            Dim RequestUrl As System.Text.StringBuilder = BuildBaseRequestURL("stats")
            With RequestUrl
                .Append("shortUrl=" & HttpUtility.UrlEncode(shortUrl))

            End With

            Dim responseObj As DataBatrix.bitlyAPI.bitlyStatsResponse = Nothing
            Try
                Dim serializer = New XmlSerializer(GetType(DataBatrix.bitlyAPI.bitlyStatsResponse))
                Using reader As XmlTextReader = New XmlTextReader(RequestUrl.ToString())
                    responseObj = CType(serializer.Deserialize(reader), DataBatrix.bitlyAPI.bitlyStatsResponse)
                End Using

            Catch ex As Exception
                Throw New ApplicationException("API Error: " & ex.Message)
            End Try
            If responseObj.errorCode > 0 Then
                Throw New ApplicationException("Error from bit.ly: " & responseObj.errorMessage)
            End If
            Return responseObj
        End Function

    End Class

    Public MustInherit Class bitlyResponseBase
         _
        Public errorCode As Integer = 0

         _
        Public errorMessage As String = String.Empty

         _
        Public statusCode As String = String.Empty

    End Class

     _
    Public Class bitlyShortenResponse
        Inherits bitlyResponseBase

         _
        Public results As New List(Of KeyVal)

        Public Class KeyVal
             _
             Public userHash As String

             _
             Public shortKeywordUrl As String

             _
             Public hash As String

             _
             Public longUrl As String

             _
             Public shortUrl As String

        End Class
    End Class

     _
    Public Class bitlyInfoResponse
        Inherits bitlyResponseBase

         _
        Public results As New List(Of bitlyInfoResultItem)

        Public Class bitlyInfoResultItem
             _
            Public shortenedByUser As String
             _
            Public keywords As String
             _
            Public hash As String
             _
            Public exif As String
             _
            Public surbl As String
             _
            Public contentLength As String
             _
            Public id3 As String
             _
            Public calais As String
             _
            Public longUrl As String
             _
            Public version As String
             _
            Public htmlMetaDescription As String
             _
            Public htmlMetaKeywords As String
             _
            Public calaisId As String
             _
            Public thumbnail As thumbnailObj
             _
            Public contentType As String
             _
            Public users As List(Of String)
             _
            Public globalHash As String
             _
            Public htmlTitle As String
             _
            Public metacarta As String
             _
            Public mirrorUrl As String
             _
            Public keyword As String
             _
            Public calaisResolutions As String
             _
            Public userHash As String

            Public Class thumbnailObj
                 _
                Public large As String
                 _
                Public small As String
                 _
                Public medium As String
            End Class

        End Class
    End Class

     _
Public Class bitlyStatsResponse
        Inherits bitlyResponseBase

         _
        Public hash As String
         _
        Public clicks As String

        Public Class bitlyStatsResultItem
             _
            Public None As String
             _
            Public direct As String
             _
            Public nodeKeyValue As List(Of KeyValue)
             _
            Public nodeKey As String

            Public Class KeyValue
                 _
            Public nodeValue As String
                 _
                Public nodeKey As String
            End Class
        End Class
    End Class

End Namespace